This invention relates generally to turbine nozzle assemblies and more particularly, to methods and apparatus for assembling turbine nozzle assemblies.
Known turbine engine nozzle assemblies include combustors which ignite fuel-air mixtures which are then channeled through a transition piece to a turbine nozzle assembly at the front of a turbine. At least some known turbine nozzle assemblies include a plurality of arcuate nozzle segments arranged circumferentially. Some known turbine nozzle segments include a plurality of circumferentially-spaced hollow airfoil vanes coupled by integrally-formed inner and outer band platforms. In such nozzle assemblies, the inner and outer bands each include a transition piece groove that enables the transition piece to be coupled in a sealing arrangement to the turbine nozzle.
Fabrication of turbine nozzle assemblies generally includes coupling a plurality of nozzle segments circumferentially together to form an annular nozzle assembly ring. More specifically, in known turbine nozzle assemblies, defects in any of the nozzle segments may not become known until the entire nozzle assembly is assembled. Moreover, during fabrication of the nozzle segments, the portion of the inner and outer bands including the transition piece groove may be subjected to distortion as various portions of the nozzle segments are welded, for example. Detecting such distortion may not be apparent until all of the nozzle segments are assembled in position within the nozzle assembly. If any of the grooves have distortion the nozzle assembly may not align correctly with the transition piece.